Right, this is some silly rumour not backed up by any evidence of a train or track.
Gerstlauer track is exactly similar to Schwarzkopf (minus the tri-track). Because they bought most of the shares of Schwarzkopf, hence why then own their old factory.
Why would Alton Towers invest in a roller coaster that has already been built twice in the UK, it would be smaller than the other two. (Speed being 120ft and Rage being 80ft). I think the height of the tent is 60ft approximatley, so it would be a bad move if they built one. They can't dig holes in the ground because of the constant erosion of the ground because of the forces Oblivion puts on it. Yes it could be mounted on a base, but it would be silly and have a lift hill of only 50ft, causing a pathetic roller coaster.
To nail the idea that Typhoon could fit in the tent is that Typhoon is 84ft tall, so it wouldn't fit, unless you made the tent bigger, which would then stick over the top of the trees, which would be silly as the tent would look invevitably daft.
The track of a Schwarzkopf are exactly similar to Gerstlauer.
^ Black Holes track
^ Gerstlauer Eurofighter Typhoon track.
The only Gerstlauer ride that could fit in the tent with some degree of success is their Bobsled coasters, which again uses the SAME track as Schwarzkopf coasters, they use tight turns and helix's, utilising a small amount of space to create a great ride. Look at Grona Lands Bobsled, its build inside another roller coaster.
So no I don't think there is a chance a Eurofighter could be built within the tent, this is my evidence, purely because it be a bad move for AT and Merlin.
Unless someone proves me wrong by showing me the track.